1. Installation Methods

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Elasticsearch can be installed using several methods. This guide covers tarball, RPM, and Docker approaches.

1.1 Tarball Installation

Create a setup script to automate the installation process.

#!/bin/bash
# setup_es.sh
ES_INSTALL_DIR="/opt/elasticsearch"
ES_VERSION="7.9.2"

# Create installation directory
mkdir -p ${ES_INSTALL_DIR}

# Download the Elasticsearch tarball
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-${ES_VERSION}-linux-x86_64.tar.gz -P ${ES_INSTALL_DIR}

# Extract the archive
cd ${ES_INSTALL_DIR}
tar -xzf elasticsearch-${ES_VERSION}-linux-x86_64.tar.gz

# Create a symbolic link for easier access
ln -s elasticsearch-${ES_VERSION} elasticsearch

1.2 RPM Installation

For RPM-based systems, use the following command to install Elasticsearch directly.

sudo yum install https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-8.4.3-x86_64.rpm

2. System Optimization

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Optimize the system for Elasticsearch by adjusting file descriptors and memory settings.

# Increase file descriptors
echo "* soft nofile 65535
* hard nofile 65535
* soft nproc 65535
* hard nproc 65535" >> /etc/security/limits.conf

# Increase virtual memory map counts
echo "vm.max_map_count=655360" >> /etc/sysctl.conf
sysctl -p

# Set environment variables
echo "export JAVA_HOME=/opt/elasticsearch/elasticsearch/jdk
export ES_HOME=/opt/elasticsearch/elasticsearch
export PATH=\$ES_HOME/bin:\$ES_HOME/jdk/bin:\$PATH" >> /etc/profile
source /etc/profile

3. Starting Elasticsearch

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Start the Elasticsearch service as a dedicated user.

# Create a dedicated user
sudo useradd -r elasticsearch_user

# Set ownership
sudo chown -R elasticsearch_user /opt/elasticsearch/elasticsearch

# Switch to the user and start Elasticsearch
sudo su - elasticsearch_user
/opt/elasticsearch/elasticsearch/bin/elasticsearch -d

4. Security Configuration

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Enable security features and set up passwords for Elasticsearch.

4.1 Configure elasticsearch.yml

Edit the configuration file to enable security and set basic network settings.

node.name: node-1
network.host: 0.0.0.0
cluster.initial_master_nodes: ["node-1"]
http.port: 9200
transport.tcp.port: 9300
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization
xpack.security.enabled: true
xpack.security.transport.ssl.enabled: true

4.2 Set Initial Passwords

Run the interactive password setup script.

sudo /opt/elasticsearch/elasticsearch/bin/elasticsearch-setup-passwords interactive

4.3 Change Password

Update the password for a specific user using the REST API.

curl -H "Content-Type:application/json" -XPOST -u elastic 'http://127.0.0.1:9200/_security/user/elastic/_password' -d '{ "password" : "new_password123" }'

4.4 Verify

Test the connection with the new credentials.

curl -XGET --user elastic:new_password123 'http://127.0.0.1:9200'

5. Configuration File Details

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Understand the key settings in the elasticsearch.yml file.

cluster.name: my_cluster                     # Unique cluster identifier
node.name: my_node_01                       # Unique node identifier
node.master: true                           # Eligible to be master node
node.data: true                             # Store data on this node

path.data: /data/es/data                    # Data storage path
path.logs: /logs/es/log                     # Log file path

bootstrap.memory_lock: false                # Disable memory swapping
bootstrap.system_call_filter: false         # Disable system call filtering

network.host: 192.168.1.100                 # Bind to specific IP
http.port: 9200                            # HTTP API port
transport.port: 9300                       # Cluster communication port

# Discovery and cluster formation
discovery.seed_hosts: ["192.168.1.100:9300", "192.168.1.101:9300"]
cluster.initial_master_nodes: ["192.168.1.100", "192.168.1.101"]

# Security settings
xpack.security.enabled: true
xpack.license.self_generated.type: basic
xpack.security.transport.ssl.enabled: true
xpack.security.transport.ssl.verification_mode: certificate
xpack.security.transport.ssl.keystore.path: elastic-certificates.p12
xpack.security.transport.ssl.truststore.path: elastic-certificates.p12

# CORS settings
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

6. Dependency Management

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Ensure system dependencies are properly configured, particularly glibc.

# Upgrade glibc to a compatible version
wget http://ftp.gnu.org/gnu/glibc/glibc-2.17.tar.gz
tar -xvf glibc-2.17.tar.gz
cd glibc-2.17
mkdir build; cd build
../configure --prefix=/usr --disable-profile --enable-add-ons --with-headers=/usr/include --with-binutils=/usr/bin
make -j 8
make install

7. Docker Installation

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Deploy Elasticsearch using Docker for containerized environments.

7.1 Create Dockerfile

Define the Docker image with custom configurations.

FROM docker.io/elasticsearch:7.16.1
LABEL description="Elasticsearch 7.16.1 with custom config"

# Copy custom configuration
COPY elasticsearch.yml /usr/share/elasticsearch/config/elasticsearch.yml

# Set timezone
RUN ln -snf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime && echo "Asia/Shanghai" > /etc/timezone

7.2 Build and Run Container

Build the Docker image and start the container with port mappings.

# Build the Docker image
docker build -t my-elasticsearch:7.16.1 -f /path/to/Dockerfile .

# Run the container
docker run -d --name elasticsearch-container -p 9200:9200 -p 9300:9300 my-elasticsearch:7.16.1

7.3 Set Passwords in Docker

Configure passswords for the Docker container.

# Access the container
docker exec -it elasticsearch-container bash

# Run interactive password setup
elasticsearch-setup-passwords interactive

# Test connection
curl -XGET --user elastic:your_password 'http://127.0.0.1:9200'

8. Plugin Installation

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Install and manage Elasticsearch plugins, such as analysis plugins.

8.1 Online Installation

Install a plugin directly from the internet.

elasticsearch-plugin install https://github.com/medcl/elasticsearch-analysis-ik/releases/download/v7.12.1/elasticsearch-analysis-ik-7.12.1.zip

8.2 Offline Installation

Install a plugin from a local file when internet access is not available.

# Create plugin directory
mkdir -p /opt/elasticsearch/elasticsearch/plugins/ik

# Download plugin package
wget https://github.com/medcl/elasticsearch-analysis-ik/releases/download/v7.12.1/elasticsearch-analysis-ik-7.12.1.zip -P /opt/elasticsearch/elasticsearch/plugins/ik

# Extract the plugin
cd /opt/elasticsearch/elasticsearch/plugins/ik
unzip elasticsearch-analysis-ik-7.12.1.zip

8.3 Plugin Management

List and remove installed plugins.

# List installed plugins
elasticsearch-plugin list

# Remove a plugin
elasticsearch-plugin remove analysis-ik

Note: Elasticsearch service restart is required after plugin installation or removal.